JavaScript is a programming language for interactive clientsidefunctionalities in web applications. It is a sequential pro-gramming language, so it cannot take advantage of multicoreprocessors. Previously Thread-Level Speculation has beenused to take advantage of multicore processors for JavaScriptexecution in web applications with promising results execu-tion time wise, but with a large memory overhead. In thisstudy we have evaluated the effects of limiting the amountof memory, the number of threads and the depth of specula-tion in Thread-Level Speculation. Our results indicate thatwe can tune these parameters to improve execution time andreduce the memory overhead.